JP2014154681A - Cleaning method of semiconductor device manufacturing apparatus and semiconductor device manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce fluorine radicals which do not react with silicon and are discharged from a deposition chamber CHM.SOLUTION: In a cleaning method of a semiconductor device manufacturing apparatus, a fluorine-containing gas is supplied to a generation part (applicator APL) for generating activated fluorine radicals. A flow rate of the fluorine-containing gas varies depending on a SiFconcentration in the gas discharged from the deposition chamber CHM.

Description

  The present invention relates to a cleaning method for a semiconductor device manufacturing apparatus and a semiconductor device manufacturing method, and is a technique applicable to, for example, the manufacture of a film containing silicon.

Currently, a method for cleaning a semiconductor device manufacturing apparatus and various techniques related thereto are proposed. Each patent document from Patent Document 1 to Patent Document 3 describes a method for reducing NF ₃ gas used as a cleaning gas for a Chemical Vapor Deposition (CVD) apparatus. In the method described in Patent Document 1, the inside of the CVD apparatus is cleaned while the reaction product removal place is changed by a combination of the gas pressure in the CVD apparatus and the shape of the magnetic field or the magnetic field strength. In the method described in Patent Document 2, in order to facilitate the vibration excitation by plasma energy of NF ₃ gas, simultaneously with the introduction of the NF ₃ gas, another gas is introduced into at least one CVD apparatus and NF ₃ gas . In the method described in Patent Document 3, the mass flow controller that supplies the NF ₃ gas is turned off in accordance with the result of monitoring the voltage generated on the chamber wall of the CVD apparatus.

  As another technique related to cleaning, Patent Document 4 describes a method for suppressing the formation of AlF on the inner surface of a chamber even when a fluorine-based gas is used for plasma during cleaning. In the method described in Patent Document 4, the plasma frequency and gas pressure during cleaning are adjusted so that AlF is not generated on the inner surface of the chamber. Patent Document 5 describes a method for efficiently cleaning the inside of the plasma processing apparatus without damaging the inside of the plasma processing apparatus and the members in the plasma processing apparatus. The method described in Patent Document 5 includes a step of cleaning the inside of the plasma processing with plasma at a first pressure and a step of cleaning the inside of the plasma processing with plasma at a second pressure higher than the first pressure. included. Patent Document 6 describes a method for reducing particles during non-processing in a CVD apparatus. In the method described in Patent Document 6, after the processing on the substrate surface is completed, the supply of the source gas is stopped while the plasma is generated. Thereafter, the substrate is carried out, and a fluorination gas for vaporizing particles is introduced into the processing chamber.

  In addition to the above, Patent Document 7 describes a method of controlling the pressure in the vacuum chamber during a time division multiplexing process. Patent Document 8 describes a method for enabling the operation process to be restarted in a short time after the plasma processing operation is temporarily stopped. In the method described in Patent Document 8, a predetermined voltage is intermittently applied between electrodes for generating plasma for a certain period from when the operation process is stopped until the operation process is restarted.

JP-A-6-318579 JP-A-6-318580 JP 2002-151417 A JP 2005-243765 A JP 2008-211099 A JP 2001-335938 A JP-T-2006-523041 JP 2007-243089 A

  In addition to the substrate, a film containing silicon may be formed inside the film forming chamber of the semiconductor device manufacturing apparatus. In some cases, activated fluorine radicals are used to remove the silicon-containing film. In the case where activated fluorine radicals are used, silicon derived from the film is vaporized by reacting with the activated fluorine radicals and discharged from the film formation chamber. On the other hand, when activated fluorine radicals are excessively supplied, part of the activated fluorine radicals may be discharged from the film formation chamber without reacting with silicon. Therefore, the present inventor studied reducing fluorine radicals discharged from the film formation chamber without reacting with silicon.

  Other problems and novel features will become apparent from the description of the specification and the accompanying drawings.

According to one embodiment, a fluorine-containing gas is supplied to a generation unit that generates activated fluorine radicals. The flow rate of the fluorine-containing gas changes according to the SiF ₄ concentration in the gas discharged from the film forming chamber.

  According to the embodiment, fluorine radicals discharged from the film forming chamber without reacting with silicon can be reduced.

It is sectional drawing which shows the semiconductor device in 1st Embodiment. It is process sectional drawing which shows the manufacturing procedure of the semiconductor device in 1st Embodiment. It is process sectional drawing which shows the manufacturing procedure of the semiconductor device in 1st Embodiment. It is sectional drawing which shows the manufacturing apparatus in 1st Embodiment. It is a block diagram which shows the structure of the cleaning apparatus in 1st Embodiment. It is a block diagram which shows the structure of the cleaning apparatus in 2nd Embodiment. It is a graph which shows the function C (t) in 2nd Embodiment. It is a figure which shows the model for demonstrating transition of the function C (t). It is a figure which shows the specific example of the flow volume of fluorine-containing gas. It is a figure which shows the specific example of the flow volume of a fluorine containing gas, and the pressure in the film-forming chamber. It is a figure which shows the other specific example of the flow volume of fluorine-containing gas, and the pressure in the film-forming chamber. It is a figure which shows the other specific example of the flow volume of fluorine-containing gas, and the pressure in the film-forming chamber.

  Hereinafter, embodiments will be described with reference to the drawings. In all the drawings, the same reference numerals are given to the same components, and the description will be omitted as appropriate.

(First embodiment)
FIG. 1 is a cross-sectional view showing a semiconductor device SD manufactured by the manufacturing method according to the first embodiment. As shown in FIG. 1, the semiconductor device SD includes a substrate SUB, a gate insulating film GIF, a gate electrode GE, a source / drain region (impurity diffusion region) SDR, and an interlayer insulating film IIF. As shown in FIG. 1, the gate insulating film GIF is formed on the substrate SUB. The gate electrode GE is formed on the gate insulating film GIF. The source / drain region SDR is formed in a region of the substrate SUB located on the side of the gate electrode GE in plan view. The interlayer insulating film IIF is formed on the gate electrode GE and the source / drain region SDR. The interlayer insulating film IIF contains silicon and contains, for example, SiO ₂ as a main component. As the substrate SUB, for example, a semiconductor substrate (for example, a silicon substrate) can be used. As the gate insulating film GIF, for example, a silicon oxide film or a high dielectric constant film (for example, a hafnium silicate film) having a higher dielectric constant than that of the silicon oxide film can be used. When the gate insulating film GIF is a silicon oxide film, the gate electrode GE is formed of a polysilicon film. On the other hand, when the gate insulating film GIF is a high dielectric constant film, the gate electrode GE is formed of a laminated film of a metal film (for example, TiN) and a polysilicon film.

  As shown in FIG. 1, the semiconductor device SD further includes a silicide layer SL1, a silicide layer SL2, a sidewall SW, a source / drain extension region SDER, an element isolation film EIF, a wiring INC, and a contact plug. CP. The silicide layer SL1 is formed on the gate electrode GE. The silicide layer SL2 is formed on the surface layer of the substrate SUB in the source / drain region SDR. The sidewall SW is formed on both side surfaces of the gate insulating film GIF and the gate electrode GE. The source / drain extension region SDER is formed on the surface of the substrate SUB under the sidewall SW. The element isolation film EIF is formed on the surface of the substrate SUB opposite to the gate electrode GE via the source / drain region SDR. The wiring INC is formed on the interlayer insulating film IIF. The contact plug CP is formed in the interlayer insulating film IIF so as to connect the silicide layer SL2 and the wiring INC.

  Next, a manufacturing procedure of the semiconductor device SD in the present embodiment will be described with reference to FIGS.

First, the element isolation film EIF is formed on the substrate SUB. Thereby, the element formation region is separated. For example, the STI method or the LOCOS method can be used to form the element isolation film EIF. Next, the gate insulating film GIF and the gate electrode GE are formed on the substrate SUB located in the element formation region. Next, source / drain extension regions SDER are formed on the substrate SUB located in the element formation region. Next, a sidewall SW is formed on the sidewall of the gate electrode GE. Next, source / drain regions SDR are formed in the substrate SUB located in the element formation region. In this way, a MOS transistor is formed on the substrate SUB. Next, silicide layers SL1 and SL2 are formed on the gate electrode GE and the source / drain regions SDR, respectively. When the gate electrode GE is formed of polysilicon, a polysilicon resistor may be formed on the element isolation film EIF in the step of forming the gate electrode GE. Next, an interlayer insulating film IIF is formed on the gate electrode GE and the source / drain region SDR. The interlayer insulating film IIF contains silicon and contains, for example, SiO ₂ as a main component. A predetermined manufacturing apparatus APR is used to form the interlayer insulating film IIF (details of the manufacturing apparatus APR will be described later). The surface of the interlayer insulating film IIF is planarized by, for example, CMP. As a result, the insulating film IIF having a flat surface as shown in FIG.

  Next, as shown in FIG. 2B, a hard mask HM, an antireflection film ARF, and a photoresist film PRF are formed in this order on the interlayer insulating film IIF. As a material for the hard mask HM, for example, a silicon oxide film can be used.

  Next, the photoresist film PRF is exposed. By this exposure, as shown in FIG. 2C, an opening OP1 located on the source / drain region SDR is formed in the photoresist film PRF.

  Next, as shown in FIG. 3A, the opening OP2 is formed in the antireflection film ARF and the hard mask HM by etching using the photoresist film PRF as a mask in the opening OP1 in plan view. The opening OP2 penetrates the antireflection film ARF and the hard mask HM. The opening OP2 is located on the source / drain region SDR.

  After the opening OP2 is formed as described above, the photoresist film PRF is removed as shown in FIG. Dry ashing and wet ashing can be used to remove the photoresist film PRF.

  Next, a contact hole CH is formed in the interlayer insulating film IIF by etching using the hard mask HM and the antireflection film ARF as a mask. Thereafter, the antireflection film ARF is removed. FIG. 3C shows a state where the antireflection film ARF is removed.

  Next, the hard mask HM is removed. Thereafter, a metal film (not shown) is deposited on the interlayer insulating film IIF so as to bury the metal in the contact hole CH. The metal film deposited on the interlayer insulating film IIF is removed by, for example, CMP. The contact plug CP is formed by removing the metal film in this way. After the formation of the contact plug CP, a metal film (not shown) for forming the wiring INC is formed on the surface of the interlayer insulating film IIF. Thereafter, the wiring INC is formed by patterning. The wiring INC is electrically connected to the source / drain region SDR via the contact plug CP. Note that the method for forming the wiring INC is not limited to the above-described method, and the wiring INC may be formed by lift-off or mask vapor deposition. Thus, the semiconductor device SD shown in FIG. 1 is obtained.

  Next, the manufacturing apparatus APR used for forming the interlayer insulating film IIF will be described in detail with reference to FIG. FIG. 4 is a cross-sectional view showing the manufacturing apparatus APR according to the present embodiment.

  The manufacturing apparatus APR includes a film formation chamber CHM. The film forming chamber CHM includes a reaction chamber RCH and a dome DM. The dome DM is provided on the reaction chamber RCH. In the reaction chamber RCH, a support base STG for mounting the substrate SUB is provided. In the dome DM, a gas nozzle GN1 and a gas nozzle GN2 are provided. The gas nozzle GN1 is provided on the top side in the dome DM. The gas supplied through the gas nozzle GN1 is supplied in a direction substantially perpendicular to the surface of the support table STG. The gas nozzle GN2 is provided on the side surface in the dome DM. The gas nozzle GN2 is provided at a position higher than the support base STG. The gas supplied through the gas nozzle GN2 is supplied in a direction substantially parallel to the surface of the support table STG. A gas containing silicon is supplied through the gas nozzle GN1 or the gas nozzle GN2. The dome DM includes a coil C1 and a coil C2. The coil C1 is provided on the top side of the dome DM. The coil C1 may be wound around the gas nozzle GN1. The coil C2 is provided on the side surface of the dome DM. The coil C2 is wound at a position higher than the gas nozzle GN2. The coil C1 and the coil C2 are connected to different high-frequency power sources (not shown).

  The manufacturing apparatus APR includes an exhaust chamber ECH in addition to the film formation chamber CHM. The exhaust chamber ECH is provided below the reaction chamber RCH. The exhaust chamber ECH includes a turbo molecular pump TMP. A dry pump DP is provided outside the exhaust chamber ECH. The gas in the exhaust chamber ECH is discharged to the dry pump DP. At this time, the gas is discharged from the exhaust chamber ECH to the dry pump DP through the gas lines GL1, GL3, and GL5 or through the gas lines GL2, GL4, and GL5. The gas line GL1 is a gas line from the exhaust chamber ECH to the valve VV1. The gas line GL2 is a gas line from the exhaust chamber ECH to the valve VV2. The gas line GL3 is a gas line from the valve VV1 to a location where the gas line GL3 and the gas line GL4 merge. The gas line GL4 is a gas line from the valve VV2 to a location where the gas line GL4 and the gas line GL3 merge. The gas line GL5 is a gas line from a location where the gas line GL3 and the gas line GL4 merge to the dry pump DP. The amount of gas discharged to the dry pump DP through the gas lines GL1, GL3, and GL5 can be adjusted by opening and closing the valve VV1. Similarly, the amount of gas discharged to the dry pump DP through the gas lines GL2, GL4 and GL5 can be adjusted by opening and closing the valve VV2. The gas line GL3 includes a measurement unit MSU. The measurement unit MSU is a device for measuring the component of the gas passing through the gas line GL3. The exhaust chamber ECH further includes a shutter SHT. The shutter SHT is opened and closed by a handle HDL. When the shutter SHT is closed, the shutter SHT is disposed so as to separate the exhaust chamber ECH into a space to which the gas line GL1 is connected and a space to which the gas line GL2 is connected. In this case, the turbo molecular pump TMP is provided in a space to which the gas line GL2 is connected.

  When the interlayer insulating film IIF containing silicon is formed on the substrate SUB using the manufacturing apparatus APR, the substrate SUB is placed on the support base STG. A gas containing silicon is supplied through the gas nozzle GN1 or GN2. At this time, for example, silane gas and argon gas may be supplied from the gas nozzle GN1, and for example, silane gas, argon gas and oxygen gas may be supplied from the gas nozzle GN2. In a state where gas is supplied, power is supplied to the coils C1 and C2 using a high-frequency power source (not shown). As a result, the above gas is excited in the dome DM and the reaction chamber RCH to generate plasma. In this way, the interlayer insulating film IIF containing silicon is formed on the substrate SUB. While the interlayer insulating film IIF is formed, the valve VV1 is closed while the valve VV2 is opened, and the shutter SHT is opened. Thereby, the gas in the film forming chamber CHM is discharged to the dry pump DP through the turbo molecular pump TMP, the gas lines GL2, GL4, and GL5. On the other hand, the gas in the film forming chamber CHM is not discharged to the dry pump DP through the gas line GL1.

  When the interlayer insulating film IIF is formed as described above, the film containing silicon is formed not only on the substrate SUB but also inside the film formation chamber CHM (for example, the inner wall of the film formation chamber CHM). There is. Such a film may peel from the inner wall of the film formation chamber CHM and adhere to the substrate SUB. The film containing silicon attached to the substrate SUB causes disconnection and short circuit of the wiring INC in the semiconductor device SD, and as a result, causes a manufacturing defect of the semiconductor device SD.

In order to remove such a film containing silicon inside the film forming chamber CHM, an applicator APL is used in the present embodiment. As shown in FIG. 4, the manufacturing apparatus APR includes an applicator APL in addition to the film formation chamber CHM and the exhaust chamber ECH. The applicator APL includes a microwave generator MGU. The microwave generator MGU generates microwaves in the applicator APL. The applicator APL is connected to the gas cylinder CLD via the gas adjustment unit GCU. Gas containing fluorine is stored in the gas cylinder CLD. As the gas containing fluorine, NF ₃ gas may be used. The flow rate of the fluorine-containing gas supplied from the gas cylinder CLD to the applicator APL is adjusted by the gas adjustment unit GCU. The applicator APL is connected to the inside of the film forming chamber CHM through the gas introduction line GIL. The opening of the gas introduction line GIL inside the film forming chamber CHM may be provided below the gas nozzle GN2.

When the manufacturing apparatus APR is cleaned using the applicator APL, the fluorine-containing gas is supplied from the gas cylinder to the applicator APL through the gas adjustment unit GCU. The fluorine-containing gas is excited by the microwave generator MGU in the applicator APL and becomes activated fluorine radicals. The activated fluorine radical is introduced into the film forming chamber CHM through the gas introduction line GIL. The fluorine radical introduced into the film formation chamber CHM reacts with silicon in the film containing silicon to generate SiF ₄ . While the activated fluorine radical is being introduced, the valve VV1 is opened while the valve VV2 is closed and the shutter SHT is closed. Thereby, the gas containing SiF ₄ in the film forming chamber CHM is discharged to the dry pump DP through the gas lines GL1, GL3, and GL5. On the other hand, the gas containing SiF ₄ in the film forming chamber CHM is not discharged to the dry pump DP through the turbo molecular pump TMP and the gas line GL2.

In the present embodiment, a cleaning method including the following steps is used.
Step (A): A step of supplying a fluorine-containing gas to a generator (applicator APL) that generates activated fluorine radicals using a fluorine-containing gas. Step (B): Silicon from the generator (applicator APL). Step of supplying activated fluorine radicals to the film formation chamber CHM of the manufacturing apparatus APR used for forming the film including the step (C): step of discharging the gas from the film formation chamber CHM Step (D): step Step of detecting the SiF ₄ concentration in the gas discharged in (C) Step (E): The flow rate of the fluorine-containing gas supplied in the step (A) is determined according to the SiF ₄ concentration detected in the step (D). Changing process

  According to the above cleaning method, fluorine radicals discharged from the film forming chamber CHM without reacting with silicon can be reduced.

  The above cleaning method may be executed when the step of forming the interlayer insulating film IIF using the manufacturing apparatus APR is performed a predetermined number of times. In this case, the frequency with which the cleaning method is performed may be periodic.

  Details of the cleaning method in the present embodiment will be described with reference to FIG. FIG. 5 is a block diagram illustrating a configuration of a cleaning device for performing the cleaning method according to the present embodiment.

  The cleaning device in this embodiment includes an input unit INU, a gas supply unit GSU, a discharge unit EXU, a detection unit DTU, an adjustment unit CTU, and a gas supply condition storage unit GST. The process shown in the step (A) is performed by the gas supply unit GSU. As the gas supply unit GSU, the gas cylinder CLD and the gas adjustment unit GCU of FIG. 4 may be used. The process shown in the step (B) is performed by the radical supply unit RSU. As the radical supply unit RSU, the applicator APL, the microwave generator MGU, and the gas introduction line GIL of FIG. 4 may be used. The process shown in the step (C) is performed by the discharge unit EXU. As the discharge part EXU, the gas lines GL1, GL3 and GL5, the valve VV1 and the dry pump DP of FIG. 4 may be used. The process shown in the step (D) is performed by the detection unit DTU. As the detection unit DTU, the measurement unit MSU in FIG. 4 may be used. The process shown in step (E) is performed by the adjustment unit CTU. As the adjustment unit CTU, the gas adjustment unit GCU of FIG. 4 may be used.

  The operation of the cleaning device in this embodiment is as follows.

  The user inputs the supply condition of the fluorine-containing gas supplied by the gas supply unit GSU into the gas supply condition storage unit GST using the input unit INU. This supply condition includes the flow rate of the fluorine-containing gas supplied by the gas supply unit GSU. The gas supply condition storage unit GST stores the input conditions as gas supply condition data. When the gas supply condition storage unit GST stores the gas supply condition data, the gas supply condition storage unit GST transmits the gas supply condition data to the gas supply unit GSU.

When the gas supply unit GSU receives the gas supply condition data, the gas supply unit GSU supplies a fluorine-containing gas (for example, NF ₃ gas) to the applicator APL based on the gas supply condition data (step (A)). The applicator APL generates activated fluorine radicals using a fluorine-containing gas. When the gas supply unit GSU starts supplying the activated fluorine-containing gas, the gas supply unit GSU transmits a gas supply signal to the radical supply unit RSU.

  When the radical supply unit RSU receives the gas supply signal, the radical supply unit RSU supplies the activated fluorine radicals from the applicator APL to the film formation chamber CHM (step (B)). When the radical supply unit RSU starts supplying fluorine radicals, the radical supply unit RSU transmits a radical supply signal to the discharge unit EXU.

  After receiving the radical supply signal, the discharge unit EXU discharges the gas from the film formation chamber CHM (step (C)). When the discharge unit EXU starts to discharge gas, the discharge unit EXU transmits a gas discharge signal to the detection unit DTU.

After receiving the gas discharge signal, the detection unit DTU detects the SiF ₄ concentration in the gas discharged by the discharge unit EXU (step (D)). When the detection unit DTU starts detecting the SiF ₄ concentration, the detection unit DTU transmits a concentration detection signal to the adjustment unit CTU. The concentration detection signal includes information on the SiF ₄ concentration detected by the detection unit DTU.

When receiving the concentration detection signal, the adjustment unit CTU reads information on the SiF ₄ concentration included in the concentration detection signal. The adjustment unit CTU updates the gas supply condition data stored in the gas supply condition storage unit GST in accordance with the SiF ₄ concentration information. When the gas supply condition data is updated, the gas supply condition storage unit GST transmits the updated gas supply condition data to the gas supply unit GSU. The gas supply unit GSU supplies a fluorine-containing gas (for example, NF ₃ gas) to the applicator APL based on the updated gas supply condition data. In this way, the adjustment unit CTU changes the flow rate of the fluorine-containing gas supplied by the gas supply unit GSU in accordance with the SiF ₄ concentration detected by the detection unit DTU (step (E)).

  According to the cleaning method using the above cleaning apparatus, fluorine radicals discharged from the film formation chamber CHM without reacting with silicon can be reduced.

(Second Embodiment)
The cleaning method in the second embodiment includes the following step (F) in addition to the steps (A) to (E) in the first embodiment.
Step (F): Time t after the start of the supply of the fluorine-containing gas when the flow rate of the fluorine-containing gas supplied in the step (A) is constant, and the SiF ₄ concentration C detected in the step (D) Step of obtaining the function C (t) indicating the relationship of In the step (E) in this embodiment, the flow rate of the fluorine-containing gas supplied in the step (A) is the function C (t) obtained in the step (F). ).

  Details of the cleaning method in the present embodiment will be described with reference to FIG. FIG. 6 is a block diagram illustrating a configuration of a cleaning device for performing the cleaning method according to the present embodiment. The cleaning device in this embodiment further includes an acquisition unit OTU and a function storage unit FST that the cleaning device of the first embodiment does not have. In this regard, the cleaning device in the present embodiment is different from the cleaning device in the first embodiment.

The process shown at a process (F) is demonstrated. When the gas supply unit GSU receives the gas supply condition data from the gas supply condition storage unit GST, the gas supply unit GSU supplies the applicator APL with a fluorine-containing gas (for example, NF ₃ gas) at a constant flow rate. When the gas supply unit GSU starts supplying the fluorine-containing gas, the gas supply unit GSU transmits a signal including the time T _{s at} which the supply of the fluorine-containing gas is started to the function storage unit FST. The function storage unit FST stores the signal from the gas supply unit GSU. The detection unit DTU detects the SiF ₄ concentration in the gas discharged by the discharge unit EXU while the gas supply unit GSU is supplying the fluorine-containing gas at a constant flow rate. The detection unit DTU transmits a signal including the SiF ₄ concentration detected by the detection unit DTU to the function storage unit FST. The function storage unit FST stores the signal from the detection unit DTU. The acquisition unit OTU reads a signal including the time T _s and a signal including the SiF ₄ concentration detected by the detection unit DTU from the function storage unit FST. Then, the acquisition unit OTU acquires the function C (t) by associating the time t from the time T _s with the SiF ₄ concentration detected by the detection unit DTU (step (F)). Thereafter, the acquisition unit OTU transmits a signal including the function C (t) to the function storage unit FST. The function storage unit FST stores a signal including the function C (t).

  The adjustment unit CTU reads a signal including the function C (t) from the function storage unit FST. The adjustment unit CTU updates the gas supply condition data stored in the gas supply condition storage unit GST according to the function C (t). When the gas supply condition data is updated, the gas supply condition storage unit GST transmits the updated gas supply condition data to the gas supply unit GSU. The gas supply unit GSU changes the flow rate of the fluorine-containing gas supplied by the gas supply unit GSU based on the updated gas supply condition data.

In the cleaning device according to the present embodiment, a function C (t) unique to the manufacturing device APR may be stored in advance in the function storage unit FST. In this case, when the gas supply unit GSU supplies a fluorine-containing gas at a constant flow rate to the manufacturing apparatus APR, an experiment for determining how the function C (t) behaves may be performed in advance. Alternatively, the cleaning device in the present embodiment acquires the function C (t) while supplying a constant flow rate of fluorine-containing gas from the time T _s to the desired time, and after the desired time, the function C (t ) May be stopped, and the flow rate of the fluorine-containing gas may be changed based on the function C (t) from the time T _s to a desired time.

Next, the function C (t) will be described in detail with reference to FIG. FIG. 7 is a graph showing the function C (t). The function C (t) shown in FIG. 7 is a function obtained under the following conditions using NF ₃ gas as the fluorine-containing gas.
NF ₃ gas flow rate: constant Pressure in film formation chamber CHM: constant (3 torr)

The transition of the function C (t) can be defined by the model shown in FIG. FIG. 8 is a diagram illustrating a model for explaining the transition of the function C (t). The SiF ₄ concentration indicated by the function C (t) corresponds to the SiF ₄ concentration C in the film forming chamber CHM in FIG. Since Si in the film formation chamber CHM becomes SiF ₄ by reaction with the fluorine-containing gas, the Si concentration C ₁ in the film formation chamber CHM changes by dC ₁ during a minute time dt. On the other hand, the SiF ₄ concentration C in the film forming chamber CHM changes by dC during the minute time dt. The change amount dC is based on the increase in dC ₁ due to the change in Si and the discharge amount −k ₂ Cdt corresponding to the concentration C. When the differential equation related to C shown in FIG. 8 is solved, the concentration C becomes as shown in Equation (1).

  The function shown in the equation (1) increases monotonously at first as the time t increases, then decreases so as to be convex upward, and decreases so as to be convex downward after the inflection point.

Based on the knowledge given by equation (1), the function C (t) can be divided into three sections, section I, section II and section III, as shown in FIG. The section I is a section from time T _s to time T _M. Section II is a section from time T _M to time T _i . Category III is a division from the time _{T i} until the time _{T e.} Time T _s is the time when the supply of the fluorine-containing gas is started. Time T _M is a time at which the function C (t) takes the maximum value C _M. The time T _i is a time at which C ′ (t) <0 and C ″ (t) = 0 with respect to the function C (t) (takes an inflection point in a range where the function C (t) monotonously decreases). . Time _Te is the time when the supply of the fluorine-containing gas ends. The time T _e is not particularly limited as long as T _i <T _e is satisfied. For example, the time when the SiF ₄ concentration becomes 1500 ppm (C _e = 1500 ppm) in a range where the function C (t) is monotonously decreasing is also possible. Good. If the time T _i cannot be clearly specified for the function C (t) acquired in the step (F), the obtained function C (t) is fitted to the equation (1) to obtain the time T _i may be estimated.

Based on the above model, the Si concentration in the film forming chamber CHM decreases according to the exponential function exp (−k ₁ t). Therefore, when the fluorine-containing gas is supplied at a constant flow rate, it is considered that the amount of fluorine radicals that are discharged without reacting with the silicon-containing film increases with time. In particular, in Section III, when a fluorine-containing gas having the same flow rate as in Sections I and II is supplied, a considerable amount of fluorine radicals may be discharged without reacting with silicon. Therefore, in the step (E), the average value of the flow rate of the fluorine-containing gas during the time period from the time T _i to the time T _e is greater than the average value of the flow rate of the fluorine-containing gas during the time period from the time T _s to the time T _i. It may be small. The average value of the flow rate of the fluorine-containing gas time zone from the time T _i to time T _e, the time integration value of the flow rate of the fluorine-containing gas time zone from the time T _i to time T _e (T _e -T _i ) divided by. The average value of the flow rate of the fluorine-containing gas time zone from the time T _s to the time T _i, the time integration value of the flow rate of the fluorine-containing gas time zone from the time T _s to the time T _i (T _i -T _s ) divided by.

A specific example of the flow rate of the fluorine-containing gas will be described with reference to FIG. 9, the average value of the flow rate of the fluorine-containing gas time zone from the time T _i to time T _e is less specific examples than the average value of the flow rate of the fluorine-containing gas time zone from the time T _s to the time T _i Indicates.

  The fluorine-containing gas may be supplied as shown in FIG. In FIG. 9A, the flow rate of the fluorine-containing gas is constant from section I through section II to the middle of section III. On the other hand, the flow rate of the fluorine-containing gas is constant from the middle of the section III at a flow rate smaller than that in the sections I and II.

  The fluorine-containing gas may be supplied as shown in FIG. 9B, the flow rate of the fluorine-containing gas is constant in the section I. The flow rate of the fluorine-containing gas is constant at a flow rate smaller than the flow rate in the section I from the section II to the middle of the section III. On the other hand, the flow rate of the fluorine-containing gas is constant from the middle of the section III at a flow rate smaller than that in the sections I and II.

The fluorine-containing gas may be supplied as shown in FIG. In FIG. 9 (c), the flow rate of the fluorine-containing gas monotonously increases in section I, decreases monotonically in section II, and decreases monotonously in section III. The value of the flow rate of the fluorine-containing gas is continuous from Section I to Section III. The flow rate at time T _i is smaller than the flow rate at time T _s .

In any embodiment of FIG. 9 (a) to (c), the average value of the flow rate of the fluorine-containing gas time zone from the time T _i to time T _e, the period from time T _s to the time T _i Smaller than the average flow rate of the fluorine-containing gas in the belt. If the flow rate of the fluorine-containing gas is adjusted in this manner, particularly in a time zone in the time zone from the time T _i to time T _e, reducing the fluorine radicals discharged from the deposition chamber CHM without reacting with silicon Can do.

Another specific example of the flow rate of the fluorine-containing gas will be described with reference to FIG. FIG. 10 is a diagram illustrating a specific example of the flow rate of the fluorine-containing gas (upper side in FIG. 10) and the pressure in the film formation chamber CHM (lower side in FIG. 10). The fluorine-containing gas may be supplied as shown in FIG. In FIG. 10, the time period from time T _s to time T _{i includes} a time period during which the fluorine-containing gas is continuously supplied. Whereas the time period from the time T _i to time T _e includes the period during which the fluorine-containing gas is supplied intermittently. Thus, the fluorine-containing gas, as shown in FIG. 10, in the time period from the time T _i to time T _e, is supplied in pulse form. Time flow of each pulse of kicking the fluorine-containing gas in the time zone from T _i to time T _e may be the same as the average value of the flow rate of the fluorine-containing gas in the time zone from the time T _s to the time T _e. Alternatively, the flow rate of each pulse of the fluorine-containing gas in the time zone from the time T _i to time T _e, the average value of the flow rate of the fluorine-containing gas time zone from the time T _i to time T _e is, from the time T _s unless smaller than the average value of the flow rate of the fluorine-containing gas time period until the time T _i, it may be larger than the average value of the flow rate of the fluorine-containing gas in the time zone from the time T _s to the time T _i. When the fluorine-containing gas is supplied in this manner, in the time period from the time T _i to time T _e, fluorine radicals discharged from the deposition chamber CHM not react with the silicon is reduced. In addition the supply method described in FIG. 10, in order to reduce the average value of the flow rate of the fluorine-containing gas time zone from the time T _i to time T _e, there is no need to reduce the pulse rate of the fluorine-containing gas . If the flow rate of the fluorine-containing gas is small, fluorine radicals may not spread throughout the film forming chamber CHM. In contrast, if the magnitude of the flow rate of the fluorine-containing gas pulse can be maintained as described above, the fluorine radicals can be reliably distributed throughout the film formation chamber CHM. Pulse supply of the fluorine-containing gas in the time zone from the time T _i to time T _e may be a periodic or not periodic. Fluorine flow rate of each pulse containing gas, in the time period from the time T _i to time T _e, may be different and may be the same as each other. Time integrated value of the flow rate of each pulse of the fluorine-containing gas, in the time period from the time T _i to time T _e, may be different and may be the same as each other. When the on-time of each pulse of the fluorine-containing gas is the same, the flow rate of each pulse of the fluorine-containing gas may be reduced as the time of the later time.

The pressure in the film forming chamber CHM may be controlled as shown in FIG. In the time zone the fluorine-containing gas out of the time zone from the time T _i to time T _e is supplied intermittently in FIG. 10, the pressure of the film forming chamber CHM while supplying the fluorine-containing gas is high-pressure ( The pressure in the film forming chamber CHM changes to a low pressure (3 torr) while the supply of the fluorine-containing gas is stopped. The pressure in the film forming chamber CHM may be controlled by the discharge unit EXU (for example, the dry pump DP and the valve VV1). In this case, the discharge unit EXU changes the pressure in the film formation chamber CHM to a low pressure by promoting the discharge of the gas in the film formation chamber CHM, and suppresses the gas discharge in the film formation chamber CHM. The pressure in the membrane chamber CHM is changed to a high pressure. When the pressure in the film formation chamber CHM is controlled as described above, the film containing silicon in the film formation chamber CHM is efficiently removed. First, when the pressure in the film formation chamber CHM is increased, fluorine radicals can be stagnated in the film formation chamber CHM, so that the reaction between the fluorine radical and the film containing silicon is promoted. Because it is done. Secondly, when the pressure in the film forming chamber CHM is lowered, the residual gas in the film forming chamber CHM is discharged, so that the gas remaining in the film forming chamber CHM next time the fluorine-containing gas is supplied. It is because it will be in the state which hardly contains.

Another specific example of the flow rate of the fluorine-containing gas will be described with reference to FIG. FIG. 11 is a diagram showing another specific example of the flow rate of the fluorine-containing gas (upper side in FIG. 11) and the pressure in the film forming chamber CHM (lower side in FIG. 11). Embodiment shown in FIG. 11, the time _T time of the time zone from _i to time _{T e T i + (T e} -T i) / 2 from the fluorine-containing gas in the time period from the time _{T e} flow integrated value is smaller than the integrated value of the flow rate of the fluorine-containing gas in the time zone from the time _{T i} of the time period from the time _{T i} to time _{T e} to time _{T i + (T e -T i} ) / 2 Except for this point, this example is the same as the specific example shown in FIG. The time _{T i + (T e -T i} ) / 2, it is time to divided into a first half and the second half the time zone from the time _{T i} until the time _{T e.} It is conceivable that the Si concentration in the film forming chamber CHM decreases with time. Therefore, the integrated value of the flow rate of the fluorine-containing gas in the time zone of the second half of the time period from the time T _i to time T _e, the fluorine in the time zone of the first half of the time period from the time T _i to time T _e Even if it is smaller than the integrated value of the flow rate of the contained gas, it is considered that there is almost no influence on the cleaning effect of the film forming chamber CHM. Therefore, according to the specific example shown in FIG. 11, as compared with the specific example shown in FIG. 10, the fluorine discharged from the film forming chamber CHM without reacting with silicon without impairing the cleaning effect of the film forming chamber CHM. Radicals can be reduced. Time integrated value of the flow rate of each pulse of the fluorine-containing gas, in the time period from the time T _i to time T _e, may be different and may be the same as each other. Fluorine if the time integrated value of the flow rate of each pulse of containing gas same as each other, the time T _i fluorine-containing off-time of each pulse of the gas in the time zone of the first half of the time period until time T _e from 11 as shown, it may be shorter than off times of the pulses of the fluorine-containing gas in the time zone of the second half of the time period from the time T _i to time T _e. If the time integrated values of the flow rate of the fluorine-containing gas pulses are different from each other, the integrated value of the flow rate of each pulse of the fluorine-containing gas is set to the value of the later time while keeping the same off time of each pulse of the fluorine-containing gas. It may be made as small as possible. Deposition chamber for the pressure of the CHM, in a time zone the fluorine-containing gas is supplied intermittently among the time zone from the time T _i to time T _e, like the embodiment shown in FIG. 10, a fluorine-containing The pressure in the film formation chamber CHM changes to a high pressure (30 torr) while the gas is supplied, and the pressure in the film formation chamber CHM decreases to a low pressure (3 torr) while the supply of the fluorine-containing gas is stopped. It has changed.

Another specific example of the flow rate of the fluorine-containing gas will be described with reference to FIG. 12 is a diagram showing another specific example of the flow rate of the fluorine-containing gas (upper side in FIG. 12) and the pressure in the film forming chamber CHM (lower side in FIG. 12). The specific example shown in FIG. 12 is the same as the specific example shown in FIG. 11 except that the time zone from time T _s to time T _{M includes} a time zone in which the fluorine-containing gas is intermittently supplied. is there. Based on the knowledge given by the equation (1), it is considered that the fluorine radical and silicon react at a very high rate in the film formation chamber CHM in the time period from the time T _s to the time T _M. When the reaction proceeds at such a high speed, it is considered that Si in the film forming chamber hardly changes to SiF ₄ due to chemical equilibrium with the generated SiF ₄ . For this reason, even if the fluorine-containing gas is continuously supplied in the time period from time T _s to time T _M, it is considered that some of the fluorine radicals are exhausted from the film formation chamber CHM without reacting with silicon. It is done. Based on the above discussion, according to the embodiment shown in FIG. 12, as compared with the embodiment shown in FIG. 11, in the time period from the time T _s to the time T _M, the film-forming chamber CHM of cleaning effect The fluorine radicals discharged from the film formation chamber CHM without reacting with silicon can be reduced without impairing the process. The supply of the fluorine-containing gas pulse in the time period from time T _s to time T _M may be periodic or non-periodic. The flow rate of each pulse of the fluorine-containing gas may be the same as or different from each other in the time period from time T _s to time T _M. The time integrated value of the flow rate of each pulse of the fluorine-containing gas may be the same as or different from each other in the time zone from time T _s to time T _M. When the on-time of each pulse of the fluorine-containing gas is the same, the flow rate of each pulse of the fluorine-containing gas may be increased for the later time.

The pressure in the film forming chamber CHM may be controlled as shown in FIG. In FIG. 12, in the time zone in which the fluorine-containing gas is intermittently supplied from the time T _s to the time T _M , the pressure in the film formation chamber CHM is increased while the fluorine-containing gas is being supplied. While the supply of the fluorine-containing gas is stopped, the pressure in the film formation chamber CHM is changed to a low pressure. The pressure in the film forming chamber CHM may be controlled by the discharge unit EXU (for example, the dry pump DP and the valve VV1). In this case, the discharge unit EXU changes the pressure in the film formation chamber CHM to a low pressure by promoting the discharge of the gas in the film formation chamber CHM, and suppresses the gas discharge in the film formation chamber CHM. The pressure in the membrane chamber CHM is changed to a high pressure. When the pressure in the film forming chamber CHM is controlled as described above, the following effects are produced. When the pressure in the film forming chamber CHM is increased, fluorine radicals are stagnated in the film forming chamber CHM. As a result, the reaction between the fluorine radical and the film containing silicon is promoted. On the other hand, when the pressure in the film forming chamber CHM is lowered, the residual gas in the film forming chamber CHM is discharged. For this reason, the film forming chamber CHM can be brought into a state containing almost no residual gas when the fluorine-containing gas is next supplied.

  According to the cleaning method using the above cleaning apparatus, fluorine radicals discharged from the film formation chamber CHM without reacting with silicon can be reduced.

In addition, according to the said embodiment, the following invention is disclosed.
(Appendix 1)
A gas supply unit that supplies a fluorine-containing gas to a generation unit that generates fluorine radicals activated using the fluorine-containing gas;
A radical supply unit that supplies activated fluorine radicals from the generation unit to a film formation chamber of a manufacturing apparatus used to form a film containing silicon;
A discharge unit for discharging the gas in the film formation chamber;
A detection unit for detecting the concentration of SiF ₄ in the gas discharged from the discharge unit;
A cleaning device for a semiconductor device manufacturing apparatus, comprising: an adjustment unit that changes a flow rate of the fluorine-containing gas supplied by the gas supply unit according to the SiF ₄ concentration detected by the detection unit.
(Appendix 2)
The cleaning apparatus according to appendix 1, wherein
A function indicating the relationship between the time t after the supply of the fluorine-containing gas is started and the SiF ₄ concentration C detected by the detection unit when the flow rate of the fluorine-containing gas supplied by the gas supply unit is constant. An acquisition unit for acquiring C (t);
Further comprising
The gas supply unit performs a time T _e (T _{i) at which} the supply of the fluorine-containing gas ends from a time T _{i when} C ′ (t) <0 and C ″ (t) = 0 with respect to the function C (t). The average value of the flow rate of the fluorine-containing gas in the time period until <T _e ) is the time period from the time T _s (T _s <T _i ) at which the supply of the fluorine-containing gas is started to the time T _i. A cleaning device for supplying the fluorine-containing gas so as to be smaller than an average value of a flow rate of the fluorine-containing gas.
(Appendix 3)
The cleaning device according to appendix 2, wherein
The gas supply unit, the time period from the time point T _i to the time T _e is a cleaning device for supplying the fluorine-containing gas so as to include a time zone wherein the fluorine-containing gas is supplied intermittently.
(Appendix 4)
The cleaning device according to appendix 2, wherein
The gas supply unit, from the time _{T i} of the fluorine-containing gas in the time zone from the time _T time of the time zone to _{e T i + (T e -T} i) / 2 to the time _{T e} integrated value of flow rate, the fluorine-containing gas in the time zone from the time _{T i} of the time period until the time _{T e} to the time point _{T i + (T e -T i} ) / 2 from the time _{T i} A cleaning device for supplying the fluorine-containing gas so as to be smaller than an integrated value of the flow rate of the gas.
(Appendix 5)
The cleaning device according to appendix 3, wherein
In the time zone in which the fluorine-containing gas is intermittently supplied, the discharge unit changes the pressure of the film formation chamber to a high pressure while the fluorine-containing gas is being supplied, and the fluorine-containing gas A cleaning device that changes the pressure of the film forming chamber to a low pressure while gas supply is stopped.
(Appendix 6)
The cleaning device according to appendix 2, wherein
The gas supply unit intermittently supplies the fluorine-containing gas during a time period from the time T _s to a time T _M (T _s <T _M ) where the function C (t) takes a maximum value. A cleaning device for supplying the fluorine-containing gas so as to include a time zone.
(Appendix 7)
The cleaning device according to appendix 6, wherein
In the time zone in which the fluorine-containing gas is intermittently supplied, the discharge unit changes the pressure of the film formation chamber to a high pressure while the fluorine-containing gas is being supplied, and the fluorine-containing gas A cleaning device that changes the pressure of the film forming chamber to a low pressure while gas supply is stopped.

  As mentioned above, the invention made by the present inventor has been specifically described based on the embodiment. However, the present invention is not limited to the embodiment, and various modifications can be made without departing from the scope of the invention. Needless to say.

SD Semiconductor device SUB Substrate EIF Element isolation film SDER Source / drain extension region SDR Source / drain region GE Gate electrode GIF Gate insulating film SW Side wall SL1 Silicide layer SL2 Silicide layer IIF Interlayer insulating film CH Contact hole CP Contact plug INC Wiring HM Hard Mask ARF Antireflection film PRF Photoresist film OP1 Opening OP2 Opening APR Manufacturing equipment CHM Deposition chamber DM Dome RCH Reaction chamber ECH Exhaust chamber STG Support base CL1 Coil CL2 Coil GN1 Gas nozzle GN2 Gas nozzle APL Applicator MGU Microwave generator GIL Gas introduction line CLD Gas cylinder GCU Gas adjustment part HDL Handle SHT Shutter TMP Turbo molecular pump VV1 Valve VV2 Valve GL1 Gas line GL2 Gas line GL3 Gas line GL4 Gas line GL5 Gas line DP Dry pump MSU Measuring unit INU Input unit GST Gas supply condition storage unit GSU Gas supply unit RSU Radical supply unit EXU Discharge unit DTU detection unit CTU adjustment unit OTU acquisition unit FST Function storage

Claims (14)

Supplying a fluorine-containing gas to a generator that generates fluorine radicals activated using the fluorine-containing gas; and
Supplying activated fluorine radicals from the generating unit to a film forming chamber of a manufacturing apparatus used for forming a film containing silicon;
Exhausting the gas from the film formation chamber;
Detecting the SiF ₄ concentration in the gas discharged in the step of discharging the gas;
Changing the flow rate of the fluorine-containing gas supplied in the step of supplying the fluorine-containing gas according to the SiF ₄ concentration detected in the step of detecting the SiF ₄ concentration. Cleaning method for manufacturing equipment. The cleaning method according to claim 1,
Detected in the step of detecting the time t and the SiF ₄ concentration after the supply of the fluorine-containing gas is started when the flow rate of the fluorine-containing gas supplied in the step of supplying the fluorine-containing gas is constant. Obtaining a function C (t) indicating a relationship with the SiF ₄ concentration C to be performed;
The fluorine in the step of supplying the gas containing the function C (t) for the C'(t) <0 and C'' (t) = 0 and becomes the time T _{time i} from the fluorine-containing gas supply is terminated _{T e (T i <T e} ) the average value of the flow rate of the fluorine-containing gas time period until the time _{T s (T s <T i} ) the time from _{T i} to supply the fluorine-containing gas is started The cleaning method is smaller than the average value of the flow rate of the fluorine-containing gas in the period up to The cleaning method according to claim 2,
Wherein the time period from the time T _i until the time T _e, the cleaning method comprising the time period during which the fluorine-containing gas is supplied intermittently. The cleaning method according to claim 2,
Integrated value of the flow rate of the fluorine-containing gas in the time zone from the time _{T i} from the time _T time of the time zone to _{e T i + (T e -T} i) / 2 to the time _{T e} is than the integrated value of the flow rate of the fluorine-containing gas in the time zone from the time _{T i} until the time _{T i + (T e -T i} ) / 2 of the time period from the time point _{T i} to the time point _{T e} Even a small cleaning method. The cleaning method according to claim 3,
In the time zone in which the fluorine-containing gas is intermittently supplied, the pressure of the film forming chamber is changed to a high pressure while the fluorine-containing gas is being supplied, and the supply of the fluorine-containing gas is stopped. A cleaning method in which the pressure in the film forming chamber is changed to a low pressure during the operation. The cleaning method according to claim 2,
A time zone from the time T _s to a time T _M (T _s <T _M ) where the function C (t) takes a maximum value includes a time zone in which the fluorine-containing gas is intermittently supplied. . The cleaning method according to claim 6, wherein
In the time zone in which the fluorine-containing gas is intermittently supplied, the pressure of the film forming chamber is changed to a high pressure while the fluorine-containing gas is being supplied, and the supply of the fluorine-containing gas is stopped. A cleaning method in which the pressure in the film forming chamber is changed to a low pressure during the operation. Preparing a gate insulating film formed on the substrate, a gate electrode formed on the gate insulating film, and an impurity diffusion region formed on a side of the gate electrode in the plan view in the substrate; When,
Forming an interlayer insulating film containing silicon on the gate electrode and the impurity diffusion region;
Supplying a fluorine-containing gas to a generator that generates fluorine radicals activated using the fluorine-containing gas; and
Supplying activated fluorine radicals from the generating unit to a film forming chamber of a manufacturing apparatus used for forming a film containing silicon;
Exhausting the gas from the film formation chamber;
Detecting the SiF ₄ concentration in the gas discharged in the step of discharging the gas;
Changing the flow rate of the fluorine-containing gas supplied in the step of supplying the fluorine-containing gas according to the SiF ₄ concentration detected in the step of detecting the SiF ₄ concentration. Manufacturing method. A method for manufacturing a semiconductor device according to claim 8, comprising:
Detected in the step of detecting the time t and the SiF ₄ concentration after the supply of the fluorine-containing gas is started when the flow rate of the fluorine-containing gas supplied in the step of supplying the fluorine-containing gas is constant. Obtaining a function C (t) indicating a relationship with the SiF ₄ concentration C to be performed;
The fluorine in the step of supplying the gas containing the function C (t) for the C'(t) <0 and C'' (t) = 0 and becomes the time T _{time i} from the fluorine-containing gas supply is terminated _{T e (T i <T e} ) the average value of the flow rate of the fluorine-containing gas time period until the time _{T s (T s <T i} ) the time from _{T i} to supply the fluorine-containing gas is started The manufacturing method of the semiconductor device smaller than the average value of the flow volume of the said fluorine-containing gas in the time slot | zone until. A method of manufacturing a semiconductor device according to claim 9,
The time the time period from T _i to the time point T _e method of manufacturing a semiconductor device wherein the fluorine-containing gas comprises a time zone that is supplied intermittently. A method of manufacturing a semiconductor device according to claim 9,
Integrated value of the flow rate of the fluorine-containing gas in the time zone from the time _{T i} from the time _T time of the time zone to _{e T i + (T e -T} i) / 2 to the time _{T e} is than the integrated value of the flow rate of the fluorine-containing gas in the time zone from the time _{T i} until the time _{T i + (T e -T i} ) / 2 of the time period from the time point _{T i} to the time point _{T e} A method for manufacturing a small semiconductor device. A method of manufacturing a semiconductor device according to claim 10,
In the time zone in which the fluorine-containing gas is intermittently supplied, the pressure of the film forming chamber is changed to a high pressure while the fluorine-containing gas is being supplied, and the supply of the fluorine-containing gas is stopped. A method for manufacturing a semiconductor device, wherein the pressure in the film forming chamber is changed to a low pressure while the film is being processed. A method of manufacturing a semiconductor device according to claim 9,
A time zone from the time T _s to a time T _M (T _s <T _M ) where the function C (t) takes a maximum value includes a time zone in which the fluorine-containing gas is intermittently supplied. Manufacturing method. A method of manufacturing a semiconductor device according to claim 13,
In the time zone in which the fluorine-containing gas is intermittently supplied, the pressure of the film forming chamber is changed to a high pressure while the fluorine-containing gas is being supplied, and the supply of the fluorine-containing gas is stopped. A method for manufacturing a semiconductor device, wherein the pressure in the film forming chamber is changed to a low pressure while the film is being processed.

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